Small box parachutes down to Bay Estates from an altitude of more than 32.5 kilometres above the Island
SHEGUIANDAH – If Islanders along a line between Providence Bay and Sheguiandah looked to the sky around 9:15 am this past Thursday, March 11, they may have noted a small box floating downward under a parachute before it touched down in the area of Bay Estates.
This box contained scientific measurement equipment and was on its way down from an altitude of more than 32.5 kilometres after taking off that morning in a weather balloon from National Weather Service (NWS)’s forecast office in Gaylord, Michigan.
It soared more than 105,000 feet skyward as part of a worldwide campaign that sees meteorologists releasing weather balloons twice daily in just under 900 locations, with 92 of those stations in the United States and 30 in Canada. This country also rosters six mobile units to use in environmental emergencies, according to a 2008 report.
The balloons carry radiosondes—small, battery-operated instruments that record atmospheric data. This forms the starting point for calculating weather forecasts, an NWS meteorologist told The Expositor.
“When combined with other locations doing that at the same time, (the radiosondes) give a snapshot of the current conditions around the world. All of that information will be fed into computer weather models and that’s what drives the forecast that leaves this office and most others around the world,” explained Matt Gillen, who has been with NWS for six years, all spent at the Gaylord station.
The radiosonde measures air pressure, temperature, dewpoint and has on-board GPS to calculate wind speed and direction. It sends data back to its launch point until the balloon bursts, at which point it begins to fall back to Earth.
Generally, the balloons will travel within a radius of 50 to 100 miles from home base. Thursday’s extraordinarily high winds led the Gaylord office to run an estimate model of the path it likely followed, based on the wind speeds at the time.
The balloon (filled with 1.6 kilograms of hydrogen) took off at about 6 am and likely burst at 7:42 near the US/Canada border in Lake Huron. By the time it popped, the balloon had likely swelled to the size of a small school bus.
Wind speeds between zero and 1,500 metres of altitude averaged about 108 km/h. Its coldest-recorded temperature on the flight was -65°C.
It then followed a path that took it over the Mindemoya area until its eventual touchdown, estimated to be near Bay Estates. Descent typically takes about 90 minutes, which is how Mr. Gillen was able to estimate its approximate landing location and time.
Despite the wealth of scientific data these launches provide, some have been critical about the release of e-waste (electronics waste) in the environment. A 2018 CBC News story examined the issue, as Canada did not feature any systems to retrieve the fallen equipment because of the cost-prohibitive nature of that task.
NWS, meanwhile, has a program to try to recover some of the radiosondes. The latex balloons will eventually biodegrade, though this can take up to four years and cause harm to wildlife in that period.
“There is a pre-addressed and pre-stamped envelope attached to the equipment. If folks are out and they come across it, we ask that they mail it back. It goes to a refurb centre and it will get reused somewhere,” he said.
The radiosondes also feature Styrofoam to ensure they can float in the case of a water landing, as may be the case with this launch.
German radiosonde manufacturer Graw acknowledged the Styrofoam floatation material, the nylon connection cord, its internal circuit board and battery all have environmental impacts. It stated on its website that it has already implemented technologies such as biodegradable cords, heavy-metal-free batteries, and is continually aiming to implement new advancements to reduce its footprint.
Mr. Gillen encouraged anyone that may find the radiosonde in the Manitoulin area to mail it back so it can re-enter service and ease the demand on buying replacement units.